Welding clamp



AW' my 1954 M. Mmmm@ WELDING CLAMP Filed Fab. 2l, 1950 INVENTOR.

Patented Apr. 13, 1954 UNITED STATES" PATENT OFFICE WELDING CLAMP Melvin P. Morris, lkmulgee, Okla.

Application February 21,1950, Serial No. 145,500

(Cl. 11S-102) 4= Claims.

My invention consists in new and useful improvements in a welding clamp for holding two pieces of pipe line in end-to-end relation prepara tory to and in the course of a welding operation. lts primary object is to provide a clamp of this nature which is relatively simple and economical in construction and easy to apply and operate, while at the same time affording a powerful and evenly distributed clamping force.

l am familiar with a number of previous clamps designed for this same general purpose, most of which have relied upon mechanical means for operating the clamp such for example as lever actuated eccentric devices, screw threaded bolts and the like. However, in practice such clamps have not been entirely satisfactory for the reason that it is frequently necessary for several persons to assist in tightening and loosening the clamps and often supplemental leverage such as the addition of a piece of pipe over the clamp handle, is necessary to operate the clamp. Furthermore, the previous clamps with which am familiar were often unable to develop suliicient operating force to restore to its original cylindrical shape, a section of pipe which had become distorted in shipping and handling.

It is therefore an object of my invention to overcome these disadvantages and to this end l have provided a clamp consisting of two hinged jaw members of arcuate shape and provided with a fluid pressure unit so mounted with respect to the jaws as to draw their free ends together around the pipe sections being welded with a sustained even distribution of force. The primary advantage of this particular arrangement lies in the fact that one man can operate the clamp with a minimum of effort and due to mounting of the fluid pressure unit, the clamp will develop a maximum operating force which will not only rmly retain the adjacent pipe sections in position, but will restore a distorted section to its proper cylindrical form.

With the above and other objects in view which will appear as the description proceeds, my invention consists in the novel features herein set forth, illustrated in the accompanying drawing and more particularly pointed out in the appended claims.

Referring to the drawing in which numerals of like character designate similar parts in both views:

Figure lis a View of the clamp in side elevation, showing the pipe in cross section; and

Figure 2 is a top plan view of the structure shown in Figure l.

As will be seen from Figure 1, my improved clamp comprises two jaw members A and B which are respectively formed of pairs, of parallel, laterally spaced, arcuate sections I and 2, hingedly connected at corresponding ends as at 3, separate hinge members being provided for complementary sections of respective pairs as shown in Figure 2.

On lthe inner face of each jaw member and bridging the parallel sections I, I and 2, 2 of each pair, I provide a series of crossties 4 which are secured as by welding, at spaced intervals around respective jaws. These crossties project laterally beyond the arcuate sections I and 2 and as will be seen from Figure 2, their ends are outwardly bevelled or ilared as at 5, to facilitate the insertion oi the pipe sections P by tending to guide them into place.

The free ends of the arcuate sections i of jaw member A are preferably thickened and extend outwardly in a direction away from the are of the jaw, terminating in a common head or support 6 which extends between and unites the free ends of the two sections I. On this support I5 is mounted a uid pressure unit generally indicated in the drawing by the letter C, the particular form of unit illustrated, comprising a hydraulic cylinder l, the extended base 8 of which is bolted as at 9 to the support E, with the axis of the cylinder 'i lying in a plane beyond the free ends of the jaw members and extending in a direction transverse to the axis oi the hinge connections 3. A power plunger II) is reciprocably mounted in the cylinder l with its cuter end projecting longitudinally from the cylinder and carrying a transverse sleeve II, which is mounted at right angles to the axis of the plunger with its opposite extremities extending laterally so as te clear the outer sides of the arcuate sections I. A connecting bail I2 is pivotally supported at one end in the sleeve II and straddles the arcuate sections I and 2, with its opposite end adapted to removably engage a pair of outwardly directed hook members I3, carried at the free ends of each of the arcuate sections 2 of the other` jaw member B. It will be noted that with this particular arrangement, the longitudinal axis of the plunger and cylinder is in a substantially direct line of pull with respect to the bail connecting hooks I3 on jaw member 2 so that a maximum force can be developed upon the application of pressure to the cylinder.

Any conventional mechanism for developing an operating pressure in the cylinder 1 may be employed, the drawing illustrating one form which consists in a second plunger M which is reclprocably mounted in a suitable chamber (not shown) in the pressure unit, and arranged in communication with the interior of the cylinder 'l, below the plunger I0. This second plunger i4 is manually operable by a connected lever i, fulcrumed as at I6 on the cylinder base 8.

It is believed unnecessary to describe the details of structure whereby an operating pressure is developedin cylinder l', sunice it to say, that by the manipulation of the hand lever I and with it the plunger I4, a pressure is developed within the cylinder 'I suflicient to force the power plunger lll outwardly, causing the connected bail l2 to urge the free ends of the jaw members A and B together with the pairs of arcuate sections i and 2, rmly around the pipe sections P.

Obviously it is necessary to provide some means for relieving the pressure when it is desired to release the clamp and in the drawing I have shown a release `valve operating lever il which through the medium of conventional mechanism, will serve this purpose.

While I prefer to use a hydraulic operating unit in connection with my improved clamp, it will of course be understood that I do not intend` to limit myself in this respect. It is possible to employ any suitable unit such as a pneumatic unit, which will develop a suicient duid operating pressure to effectively draw the jaw members together Varound the pipe sections, if the unit is properly mounted with respect to the jaw members.

It will be apparent that with a clamp constructed in accordance with my invention, a single operator is enabled to apply and operate the clamp with a minimum ofeifort and with a maximum of economy in time and expense. Furthermore, where the mechanical leverage and eccentric cam arrangements of prior devices have been limited in the degree of tightening movement available, it will be apparent that with my hydraulic or fluid pressure actuated structure, the operating pressure available is'limited only by the extent of the ability of the clamp jaws to withstand strains.

FromV the foregoing it is believed that my invention may be readily understood by those skilled in the art without further description, it being borne in mind that numerous changes may be made in the details of structure without departing from the spirit `of the invention as set forth in the following claims.

VI claim: Y

1. A self-supporting uid pressure operated welding clamp for holding two pipe elements in end-to-end relation, comprising iirst and second jaw members, each consisting of a pair cf parallel transversely spaced sections of arcuate contour, connected by crossties, hinge means connecting said jaw members at one end, the adjacent free ends of the sections of said iirst jaw member being joined by a transversely extending ilat base member, lying in a plane parallel with the axis of the jaw hinge, the free ends of the sections o1 said second jaw member being provided with bail retaining means, a iluid pressure cylinder closed at one end and having a coaxial opening in its opposite end, the closed end of said cylinder being xed to and supported by said base member and Ythereby maintained in fixed relation with respect to said rst jaw member, the opposite open end of said cylinder projecting in a direction away from the bail retaining means carried by said second jaw member, with the axis of the cylinder lying in a plane perpendicular to the plane of said base member, a plunger in said cylinder, having a longitudinal extension which projects coaxially through the open end of said cylinder` and is movable with said plunger, a bail consisting of two substantially parallel, elongated side arms disposed on either side of said cylinder and joined at opposite ends by crossarms, one of which is pivotally mounted transversely, on the projecting end of said plunger extension, to facilitate swinging movement of its opposite free end into and'out of operative engagement with the bail retaining means on said second jaw member, said plunger extension and lbail being movable with said plunger in a substantially direct line of pull with respect to the bail retaining means, and means for developing an operating fluid pressure in said cylinder.

2. A welding clamp as claimed in vclaim 1 including manually operated means for developing a fluid pressure in said cylinder to force said plunger outwardly.

3. A Welding clamp as claimed in claim 1 wherein the free ends of the sections of said nrst jaw member are extended outwardly beyond the arc of said jaw to support said base member.

4. A welding clamp as claimed in claim l wherein the outer end of said plunger extension carries a xed transverse sleeve for pivotally supporting the corresponding crossarm of said bail.

References Cited in the le of this patent UNITED STATES PATENTS Number I Name Date 1,104,579 Thorsby July 12, 1914 1,572,740 Mattice Feb. 9, 1926 1,693,064 Tipton l Nov. 27, 1928 1,818,435 Smith Aug. 11, 1931 2,167,887 Graham Aug. 1, 1939 2,308,340 Newlon Jan. 12, 1943 2,360,417 v Grenfell Oct. 17, 1044 2,365,151 Solomon Dec. 19, 1944 2,433,172 Tipton Dec. 23, 1947 2,525,680 I-ngemarson Oct. 10, 1950 

